The present invention relates to a deformable mirror device and a manufacturing method thereof and, more particularly, to a deformable mirror device having a large effective reflection area and a simple configuration and a manufacturing method therefor.
As shown in PIG. 1, a typical deformable mirror device has a plurality of reflecting mirrors 1 each rotatably connected to a post 2 via a hinge 3. Each of the reflecting mirrors 1 is rotated by static electricity, and reflects light incident thereto at a predetermined angle. The deformable mirror device is used in a video displaying device for a projection television and in a light scanning device for a scanner, a copying machine, a facsimile machine, etc. The reflecting mirrors 1 of the deformable mirror device are arranged in a two-dimensional way having one mirror per pixel of an image. Each reflecting mirror 1 is rotated according to the respective pixel of an image signal to reflect light, whereby the color and brightness are controlled.
A manufacturing method of a "Multi-level Deformable Mirror Device" disclosed in U.S. Pat. No. 5,083,857 assigned to Texas Instruments Inc. will be described with reference to FIG. 2.
As shown in FIG. 2, a static random access memory (SRAM) 12 and an oxide protective film 13 are sequentially formed on the upper surface of a substrate 11 including an address scanning circuit. Then, a first spacer layer 21 having a predetermined pattern 22 is formed on the oxide protective film 13, in step 100.
In step 110, a hinge 14 is formed on the upper surface of the first spacer layer 21 by a sputtering method, and an electrode 16 having a first support post 15 is formed on the upper surface of the hinge 14.
In step 120, a second spacer layer 23 is formed on the electrode 16, and a reflecting mirror 18 having a second support post 17 is then formed thereon. In this case, the reflecting mirror 18 is typically formed by sputtering aluminum.
Finally, the first and second spacer layers 21 and 23 are removed, thereby completing a deformable mirror device, in step 130.
However, when defects are generated during manufacturing of the hinge 14, the reflecting mirror 18, etc., formed on the upper surface of the SRAM 12 during manufacture of the deformable mirror device, the SRAM 12 is damaged. Also, a plurality of layers must be sequentially formed on the upper surface of the substrate 11, so the manufacturing process of the deformable mirror device is complicated.